Building codes such as the icc s 2012 international building code section 2308 10 roof and ceiling framing typically specify that where rafter ties are used they are required at intervals ranging from 12 to 24 o c.
Garage roof support beams spacing.
Window door garage door headers supporting roof wall floor loads.
The same concept holds true for roof trusses.
Depending on the roof design and the roof rafter spacing.
An essential part of planning a patio roof or gazebo project is determining the number size and spacing of rafters beams and posts according to the loads they will carry.
According to the 2012 irc codes any beam joist or header shall never have a bearing of less than 1 1 2.
The table states that 2 x 6 rafters spaced 16 inches on center o c can span a maximum distance of 13 feet 5 inches.
For example you can span a 1 grade no knots southern yellow pine a greater distance than a 2 grade with knots southern yellow pine.
Beams of more than one ply must be fastened together with either nails or bolts.
Window door garage door headers supporting roof loads only.
Subtract that number from the width of the panel and then divide by 2 to come up with the spacing for the rafters.
The lengths and sizes of joists vary depending on the species and quality of the lumber used.
Anything 5 and above we always at least double cripple.
Common spacing for trusses on this type of building is often between 2 and 4 feet but trusses built with advanced designs may allow spacing as great as 8 or 12 feet.
This is the distance between joist centres.
Another option are 2 x 8 rafters spaced 24 inches o c.
Double the hill and valley width since this is the amount that the panel will overlap the one next to it on each side.
Tables providing size selections for various beam spans and loading combinations for southern pine dimension lumber and southern pine glued laminated timber are available for the following applications.
Usually 400 450 or 600mm but any value can be used up to 610mm max 1 2 timber strength class and joist size automatically calculate sizes suitable for supporting the loads below.
On longer spans the beam may require much more bearing space as indicated by this table.
I would like to create some storage space in the garage ceiling space and i am looking to place beams joists that will lay on the side walls.
Maximum rafter spans for a patio roof in areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot.
I have an old 1937 brick built garage with pitched roof shared with next door.